summaryrefslogtreecommitdiffstats
path: root/server/src/com/vaadin/data/Validator.java
blob: d5672673382ee0c01f6fdcfe56c1ad9647758898 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
/*
 * Copyright 2000-2014 Vaadin Ltd.
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */

package com.vaadin.data;

import java.io.Serializable;

import com.vaadin.server.VaadinServlet;

/**
 * Interface that implements a method for validating if an {@link Object} is
 * valid or not.
 * <p>
 * Implementors of this class can be added to any
 * {@link com.vaadin.data.Validatable Validatable} implementor to verify its
 * value.
 * </p>
 * <p>
 * {@link #validate(Object)} can be used to check if a value is valid. An
 * {@link InvalidValueException} with an appropriate validation error message is
 * thrown if the value is not valid.
 * </p>
 * <p>
 * Validators must not have any side effects.
 * </p>
 * <p>
 * Since Vaadin 7, the method isValid(Object) does not exist in the interface -
 * {@link #validate(Object)} should be used instead, and the exception caught
 * where applicable. Concrete classes implementing {@link Validator} can still
 * internally implement and use isValid(Object) for convenience or to ease
 * migration from earlier Vaadin versions.
 * </p>
 * 
 * @author Vaadin Ltd.
 * @since 3.0
 */
public interface Validator extends Serializable {

    /**
     * Checks the given value against this validator. If the value is valid the
     * method does nothing. If the value is invalid, an
     * {@link InvalidValueException} is thrown.
     * 
     * @param value
     *            the value to check
     * @throws Validator.InvalidValueException
     *             if the value is invalid
     */
    public void validate(Object value) throws Validator.InvalidValueException;

    /**
     * Exception that is thrown by a {@link Validator} when a value is invalid.
     * 
     * <p>
     * The default implementation of InvalidValueException does not support HTML
     * in error messages. To enable HTML support, override
     * {@link #getHtmlMessage()} and use the subclass in validators.
     * </p>
     * 
     * @author Vaadin Ltd.
     * @since 3.0
     */
    @SuppressWarnings("serial")
    public class InvalidValueException extends RuntimeException {

        /**
         * Array of one or more validation errors that are causing this
         * validation error.
         */
        private InvalidValueException[] causes = null;

        /**
         * Constructs a new {@code InvalidValueException} with the specified
         * message.
         * 
         * @param message
         *            The detail message of the problem.
         */
        public InvalidValueException(String message) {
            this(message, new InvalidValueException[] {});
        }

        /**
         * Constructs a new {@code InvalidValueException} with a set of causing
         * validation exceptions. The causing validation exceptions are included
         * when the exception is painted to the client.
         * 
         * @param message
         *            The detail message of the problem.
         * @param causes
         *            One or more {@code InvalidValueException}s that caused
         *            this exception.
         */
        public InvalidValueException(String message,
                InvalidValueException... causes) {
            super(message);
            if (causes == null) {
                throw new NullPointerException(
                        "Possible causes array must not be null");
            }

            this.causes = causes;
        }

        /**
         * Check if the error message should be hidden.
         * 
         * An empty (null or "") message is invisible unless it contains nested
         * exceptions that are visible.
         * 
         * @return true if the error message should be hidden, false otherwise
         */
        public boolean isInvisible() {
            String msg = getMessage();
            if (msg != null && msg.length() > 0) {
                return false;
            }
            if (causes != null) {
                for (int i = 0; i < causes.length; i++) {
                    if (!causes[i].isInvisible()) {
                        return false;
                    }
                }
            }
            return true;
        }

        /**
         * Returns the message of the error in HTML.
         * 
         * Note that this API may change in future versions.
         */
        public String getHtmlMessage() {
            return VaadinServlet.safeEscapeForHtml(getLocalizedMessage());
        }

        /**
         * Returns the {@code InvalidValueExceptions} that caused this
         * exception.
         * 
         * @return An array containing the {@code InvalidValueExceptions} that
         *         caused this exception. Returns an empty array if this
         *         exception was not caused by other exceptions.
         */
        public InvalidValueException[] getCauses() {
            return causes;
        }

    }

    /**
     * A specific type of {@link InvalidValueException} that indicates that
     * validation failed because the value was empty. What empty means is up to
     * the thrower.
     * 
     * @author Vaadin Ltd.
     * @since 5.3.0
     */
    @SuppressWarnings("serial")
    public class EmptyValueException extends Validator.InvalidValueException {

        public EmptyValueException(String message) {
            super(message);
        }

    }
}